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A077719 Primes which can be expressed as sum of distinct powers of 5.

%I A077719 #10 May 31 2021 09:34:37
%S A077719 5,31,131,151,631,751,3251,3881,16381,19381,19501,19531,78781,78901,
%T A077719 81281,81401,81901,82031,93901,94531,97001,97501,97651,390751,390781,
%U A077719 393901,394501,406381,468781,469501,471901,472631,484531,485131,487651,1953151,1953901
%N A077719 Primes which can be expressed as sum of distinct powers of 5.
%C A077719 Primes whose base 5 representation contains only zeros and 1's.
%H A077719 Michael S. Branicky, <a href="/A077719/b077719.txt">Table of n, a(n) for n = 1..10000</a>
%o A077719 (Python)
%o A077719 from sympy import isprime
%o A077719 def aupton(terms):
%o A077719   k, alst = 0, []
%o A077719   while len(alst) < terms:
%o A077719     k += 1
%o A077719     t = sum(5**i*int(di) for i, di in enumerate((bin(k)[2:])[::-1]))
%o A077719     if isprime(t): alst.append(t)
%o A077719   return alst
%o A077719 print(aupton(37)) # _Michael S. Branicky_, May 31 2021
%Y A077719 Cf. A020449, A000695, A033042, A077717, A077718, A077720, A077721, A077722.
%K A077719 nonn
%O A077719 1,1
%A A077719 _Amarnath Murthy_, Nov 19 2002
%E A077719 More terms from _Sascha Kurz_, Jan 03 2003
%E A077719 a(36) and beyond from _Michael S. Branicky_, May 31 2021